Questions/Answers

1. Which of the following is the extensive property of a thermodynamic system?

A. Pressure

B. Density

C. Volume

D. Temperature

View Answer/Explanation

Correct Answer is C

Properties whose values depend on the mass of a system like – Volume etc.

2. In which one of the following working substances, does the relation T1 /T2 = (ρ1 /ρ2)0.286 hold if the process takes place with zero heat transfer?

A. Wet Steam

B. Air

C. Isentropic

D. Petrol Vapor and Air mixture

View Answer/Explanation

Correct Answer is B

Air

T1 /T2 = (ρ1 /ρ2)(γ-1)/γ

Put γ = 1.4

3. In new temperature Scale say °D, the boiling and freezing points of water at one atmosphere are 100 °D and 300 °D respectively. Correlate the scale with the Centigrade scale. The reading of 0 °D on the Centigrade scale is-

A. 0 °C

B. 25 °C

C. 100 °C

D. 150 °C

View Answer/Explanation

Correct Answer is D

150 °C

Use the basic formula, used for conversion.

4. Which of the following statements apply to a perfect gas will also be true for an irreversible process?

A. Tds = du + pdV

B. dQ = du + pdV

C. dQ = Tds

D. None of these

View Answer/Explanation

Correct Answer is A

Tds = du +pdV

All these are properties.

5. The correct sequence in decreasing order of the value of the characteristic gas constant of the given gases –